1. Field of the Invention
The invention is in the cognitive function evaluation devices and methods.
2. Description of the Related Art
Concussion, also known as mild traumatic brain injury (MTBI), has recently become widely recognized as a significant cause of disability in athletes. The currently accepted definition of concussion, that this injury represents a functional more than structure disorder, alludes to the fact that concussed athletes suffer from symptoms referable to disruptions in multiple physiologic systems, resulting in a diminution of overall physical performance. Studies show that sending an athlete back into action before the concussion or other neurological injury has healed may lead to further concussions in the short term, which may lead to permanent neurological defects in the long term.
In addition to decrements in cognition, vestibular and visual performance have been shown to be negatively effected by concussion. Additionally, it is well known that the increased metabolic demands associated with physical activity typically exacerbate these symptoms. In light of these facts, it would appear logical that in order to accurately evaluate and rehabilitate an athlete who has experienced a concussion that a comprehensive approach be utilized, one that addresses all aspects of the problem.
One tool utilized for the assessment of the ability of the athlete to return to play following concussion is IMPACT, a commercially available product that is categorized as a computer-based neurocognitive examination. There is an abundance of peer reviewed literature supporting its use in this capacity. The athlete is determined to have “recovered sufficiently” from his concussion once his IMPACT scores return to baseline or above. Current tests employed to assess the concussed athlete's ability to return to play (such as IMPACT) measure isolated capabilities. Such isolated testing does not accurately evaluate the athlete.
While IMPACT has been validated as a useful tool to determine restoration of baseline cognitive function following concussion, it does not adequately address the other physiologic system problems associated with concussion. Also, the test is taken in a sedentary state in which the athlete is able to focus all of their attentional resources to the test and as such the contribution of increased metabolic activity is not evaluated. Nor is the athlete's physical and/or physiological performance capabilities evaluated.
As discussed, tests such as IMPACT are neurocognitive tests for concussion recovery assessment measuring the speed and accuracy of tests of attention, speed, learning and working memory while the athlete is sedentary. Such tests are limited to the measurement of isolated capacities.
It is well accepted that movement defines functional capability. Orthopedic injuries affect the ability to react and move, as do brain injuries that impede the neurological system from properly signaling the musculoskeletal system. Measurement of the fundamental components of movement allows the clinician, trainer or coach to view disability and capability as a continuum of the capacity for movement.
The neuro-physical testing performed on static balance testing devices are limited to assessing aspects of the athlete's visual, vestibular or somatosensory systems that the athlete may rely on to maintain balance. The athlete typically remains stationary, i.e. the feet remain essentially in a fixed position. In summary, the perceived deficits of known concussion assessment devices include: 1) the inability to elevate the athlete's metabolic rate, as measured by heart rate, to levels consistent with game play; 2) they do not measure the athlete's reaction time to spontaneous (unplanned) stimuli that prompt sport-relevant movement responses, which are defined as multi-vector (3-dimensional) movement comprising distances approximating those of game play; and 3) they do not challenge the athlete's vision and vestibular system in a sport-relevant manner; prompting from the athlete 360 degree movements, i.e. the lateral, linear, vertical and rotational (turning) movements inherent in most sports.
In view of the above defects with current methods and systems, improvements in evaluation systems and methods would be desirable.